An earlier, or a longer, or both WWI. The war was decisive in creating a shared national experience for the Indians, as for the Canadians, Australians, etc. Creating the scenario of an earlier WWI might bring more people towards dominionist movements earlier on and set the stage for dominion status in the 20s. A longer WWI...if the war lasts into 1919, means that the Government of India takes control over the Middle Eastern theatre, which means more Indian troops in the region, which increases the possibility for future discontentment and thus social and political change.